How Does The Difference Between Mass and Weight Work?

Mass is how much stuff you're made of, and weight is how hard gravity pulls on that stuff.

Imagine you have a toy box full of blocks. If you take one block out, it feels lighter than the whole box, that’s like mass. No matter where you go, the number of blocks (your mass) stays the same. But if you take the block to the moon, gravity is weaker there, so it feels lighter, that’s your weight.

What's the difference?

  • Mass is like the number of blocks in your toy box.
  • Weight is how much the blocks push down on the floor, and that changes depending on where you are.

If you're on Earth, gravity is strong, so you weigh more. If you go to space, gravity is weak, so you weigh less, but you still have the same number of blocks (mass) inside you!

So mass is constant, but weight can change based on gravity, just like your toy box feels different in different places!

Take the quiz →

Examples

  1. A person on Earth weighs more than the same person on the Moon because of gravity, even though their mass is the same.
  2. You can carry a bag full of books easily if it's light (low mass), but it feels heavier (high weight) when you're on the Moon.
  3. Mass is like how much stuff is in an object, while weight is how hard gravity pulls on that stuff.

Ask a question

See also

Discussion

Recent activity

Categories: Science · mass· weight· gravity